In New York, messages of hope and encouragement were projected along the side of the Brooklyn Academy of Music. The messages, photos of which were featured on blogs across the Web, read "Brooklyn Loves New York" and a quote from Dr. Martin Luther King Jr.: "Darkness cannot drive out darkness, only light can do that."

The Chicago Tribune's sports section dedicated its front page to the people of Boston via their beloved sports teams. "We are Chicago Red Sox. We are Chicago Celtics. We are Chicago Bruins. We are Chicago Patriots. We are Chicago Revolution," the paper declared.

We are like you. We know that sports are often the ties that hold us together, that give us a way to talk about the things we care about when other words fail. We know sports can be fun—even in losing. Boy, do we know. We know that anybody who says it doesn't matter whether the Cubs or Sox are in the World Series so long as it's a Chicago team isn't truly a fan of either team. We know. But on Monday, we were reminded again how fragile it all can be. The explosions and injuries and death at a world-class sporting event such as the Boston Marathon makes us heartsick. As much as it is anathema for a Chicago fan to root for any other town—especially Beantown and all of its championship rings—here we are. Hang in there, Boston."

Comedian and actor Patton Oswalt wrote a widely seen Facebook post, offering his support and empathy for Boston.

You watch the videos of the carnage and there are people running TOWARDS the destruction to help out. ... This is a giant planet and we're lucky to live on it but there are prices and penalties incurred for the daily miracle of existence. One of them is, every once in awhile, the wiring of a tiny sliver of the species gets snarled and they're pointed towards darkness.

But the vast majority stands against that darkness and, like white blood cells attacking a virus, they dilute and weaken and eventually wash away the evil doers and, more importantly, the damage they wreak. This is beyond religion or creed or nation. We would not be here if humanity were inherently evil. We'd have eaten ourselves alive long ago.

So when you spot violence, or bigotry, or intolerance or fear or just garden-variety misogyny, hatred or ignorance, just look it in the eye and think, "The good outnumber you, and we always will."

Also popular—a quote from the late great Mr. Fred Rogers. "When I was a boy and I would see scary things in the news, my mother would say to me, 'Look for the helpers. You will always find people who are helping.'"

Cartoonist Randy Bish used the quote to help showcase the many acts of heroism amid the chaos and confusion.